In recent years, as a standard for a disc type record medium that is recordable and that is detachable from a recording and reproducing apparatus, the Blu-ray Disc standard has been proposed. In the Blu-ray Disc standard, as a record medium, a disc having a diameter of 12 cm and a cover thickness of 0.1 mm is used. As an optical system, a blue-purple laser having a wavelength of 405 nm and an objective lens having an aperture of 0.85 are used. With this structure, the Blu-ray Disc standard accomplishes a recording capacity of 27 gigabytes (GB) (max). Thus, on a Blu-ray disc, a Japanese BS digital high-vision broadcast program can be recorded for two hours or longer without deterioration of picture quality.
As sources of audio/video (AV) signals recorded on recordable optical discs, it is contemplated that there will be analog signals of for example existing analog television broadcasts and digital signals of for example BS digital broadcasts. In the Blu-ray Disc standard, standards that define recording methods of these broadcasts have been established.
On the other hand, as derivative standards of the current Blu-ray Disc standard, the development of reproduction-only record mediums on which movies, music, and so forth are pre-recorded are being actively performed. As disc shaped record mediums on which movies and music are recorded, DVDs (Digital Versatile Discs) have been widespread. A reproduction-only optical disc based on the Blu-ray Disc standard has a large capacity, a high speed transfer rate, and so forth and can contain a high-vision picture for two hours or more with high picture quality. Thus, the Blu-ray disc is largely different from the current DVD and superior thereto in these features.
In the following, the standard of a reproduction-only record medium based on the Blu-ray disc standard is referred to as the BD-ROM (Blu-ray Disc-Read Only Memory) standard. On the other hand, the standard of a recordable record medium based on the Blu-ray Disc standard is referred to as the BD-RE standard. Patent document “Japanese Patent Application 2004-21886” describes the BD-ROM standard, which is a reproduction-only type Blu-ray disc.
According to the BD-ROM standard, video data are recorded as clips. A reproduction region of a clip can be specified with a movie play list (MoviePlayList). In this case, a block of data as a unit of which continuously synchronous reproduction, namely real time reproduction, is assured, is referred to as a clip. For example, video data that exist as one file on a record medium is a clip. A movie play list specifies a reproduction start point (IN point) and a reproduction end point (OUT point) of each of a plurality of clips. Thus, a movie play list can specify a reproduction region of each of plurality of clips and a reproduction order of clips.
A movie play list (hereinafter abbreviated as a play list) is specified and the specified movie play list is reproduced by a navigation command of a movie object (MovieObject). Movie objects are listed as entries of titles on an index table. The index table is data that are initially read when the disc is loaded into the player. When the disc is loaded into the player, the user can see titles contained in the index table.
Moreover, in the BD-ROM standard, the reference relationship of which clips and play lists are referenced each other can be freely set. For example, a particular clip can be referenced from two play lists having different IN points and OUT points. In addition, the reference relationship of which titles and movie objects are referenced each other can be freely set.
FIG. 1 schematically shows the relationship of titles, movie objects, and play lists according to the BD-ROM standard. When the disc is loaded into the player, first playback (FirstPlayBack) and top menu (TopMenu) are initially read from the index table. A trailer and the top menu are reproduced from the disc according to movie objects contained in the first playback (FirstPlayBack) and the top menu (TopMenu). The user can command the player to reproduce each title from the disc.
FIG. 1 shows the structure of a scenario. In this scenario, the first playback and the top menu specify movie object #4. From movie object #4, play list #100 and play list #101 are referenced. As a result, a top screen for the first playback and the top menu are displayed.
In other words, in the example shown in FIG. 1, the menu screen of movie object #4 is displayed. After the menu screen is displayed, the reproduction of movie object #0 is started. While the menu screen is displayed, when title jump is selected, the control flow jumps to title #1. The reproduction of movie object #0 is started from title #1.
The top menu navigates the reproduction of six titles, title #1 to title #6. Title #1 and title #3 cause the player to reproduce movie object #0. Title #4 and title #6 cause the player to reproduce movie object #2. In addition, from movie object #4 for the reproduction of the top menu, the control flow jumps to title #1 and to movie object #0 referenced by title #1. Movie object #0 contains a command that causes the player to reproduce two play lists, play list #100 and play list #101. Movie object #3 contains a command that causes the player to reproduce three play lists, play list #4, play list #5, and play list $6.
As described above, according to the BD-ROM standard, a plurality of titles can cause the player to reproduce one movie object. The control flow can jump from one object to a title and a movie object. One movie object can cause the player to reproduce a plurality of play lists. When titles, movie objects, and play lists are freely referenced each other, the content creator can easily realize his or her idea.
DVD recorders that record AV (Audio/Video) data to a recordable DVD according to the DVD-Video (Digital Versatile Disc-Video) standard defined for existing reproduction-only record mediums have widespread. Thus, it is contemplated that the BD-ROM standard that has been developed as a standard for reproduction-only record mediums will be used as one of recording systems for home-use recorders. Thus, a standard that extends the BD-ROM standard to recordable record mediums is being developed.
When the BD-ROM standard is extended to recordable record mediums, titles recorded on the disc need to be specified from a top menu reproduced according to an index table and to be reproduced. In addition, for recordable recording mediums, titles need to be edited. For example, titles need to be deleted or added.
In the case that such a record medium is used for a video camera, when a record button or the like is pressed and the recording operation is started, new clips are recorded. When the record button is released, the recording operation is stopped and titles corresponding to the clips are added. Likewise, when recorded clips are deleted, titles corresponding thereto are deleted.
It is assumed that titles are managed by assigning title numbers in the order of which clips were recorded. In this case, it is contemplated that there are two management methods. In one management method, title numbers are stored regardless of whether titles were edited. In the other management method, when titles are edited, the order of which they were recorded is stored and title numbers are changed as the titles are edited.
For example, as exemplified in FIG. 2A, it is contemplated that there are title #1, title #2, title #3, and title #4. When title #2 is deleted, as exemplified in FIG. 2B, in the first management method, their title numbers are stored. Thus, title #2 that was deleted becomes an unused number. In contrast, in the second management method, as exemplified in FIG. 2C, the title numbers after title #2 that was deleted are decreased by 1. In the example shown in FIG. 2C, title #3 and title #4 that were edited become title #2 and title #3, respectively.
The first management method or the second management method is implemented to the recorder depending on its design concept or the like.
However, in this case, there is a problem of which compatibility of a menu screen and so forth is not maintained between a recorder in which the first management method has been implemented and a recorder in which the second management method has been implemented.
With reference to FIG. 2A, FIG. 2B, and FIG. 2C, when a menu screen created according to the first management method is reproduced by an apparatus in which the second management method has been implemented, contradiction may occur in such a manner that a menu corresponding to title #4 shown in FIG. 2B is not displayed. Likewise, when a menu screen created according to the second management method is reproduced by an apparatus in which the first management method has been implemented, contradiction may occur in such a manner that although title #2 shown in FIG. 2C is displayed, it is not able to be reproduced.